BEIJING, Oct. 16 -- Chinese authorities on Wednesday released an action plan for air pollution control in the Beijing-Tianjin-Hebei region and nearby areas, setting specific targets for the autumn and winter season.

The average density of PM2.5, fine particulate matter that causes smog, should drop by 4 percent from Oct. 1, 2019 to March 31, 2020, compared with the same period last year, according to the plan jointly released by several government agencies including the Ministry of Ecology and Environment and the National Development and Reform Commission.

The number of days with severe pollution should fall by 6 percent, said the plan.